import java.util.Scanner;

public class Average {
    static int n = 0;
    public static double avg(int[] array){
        int sum = 0;
        for(int i = 0; i < n ; i++){
            sum += array[i];
        }
        return (double)sum / n;
    }

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int[] arr = new int[10];
        n = scan.nextInt();
        for(int i = 0; i < n; i++){
            arr[i] = scan.nextInt();
        }
        double avgSum = avg(arr);
        System.out.println(avgSum);
    }
}
